Protein tyrosine phosphatases involved in signaling of the ABA-induced H2O2 generation in guard cells of Vicia faba L.

Although protein tyrosine phosphatases (PTPases) play an important role in signal transduction in animal cells, little is known about the function of PTPases in higher plants. Hydrogen peroxide (H2O2) and mitogen-activated protein kinases (MAPKs) are the critical components of ABA signaling pathway in guard cells. PTPase is an important regulator of MAPK, which is believed to mediate ABA-induced H2O2 generation in guard cells of Vicia faba L. Here, we investigate the possible role of PTPases in stomatal movement process. Phenylarsine oxide (PAO), a specific inhibitor of PTPases, could prevent ABA or H2O2-induced stomatal closure of Vicia faba L; furthermore, it could promote opening of the stomata closed by ABA or H2O2. The activity of PTPases can be effectively inhibited by PAO and H2O2. DTT had no effect on the PAO-induced inhibition of PTPases activity, but it could relieve the inhibition of H2O2 on PTPases activity. PAO could also inhibit the ABA-induced H2O2 generation in guard cells of V‘wia faba L. These results suggested that PTPases is a critical signaling component in ABA-induced stomatal closure, and serve as targets for H2O2 lying on the signaling pathways downstream of ABA induced H2O2 generation.     

Nitric oxide involved in signal transduction of Jasmonic acid-induced stomatal closure of Vicia faba L.

Nitric oxide (NO) and Jasmonic acid (JA) are two key signaling molecules involved in many and diverse biological pathways in plants. Growing evidence suggested that NO signaling interacts with JA signaling. In this work, Our experiment showed that NO exists in guard cell of Vicia faba L., and NO is involved in signal transduction of JAinduced stomata closuring: ( i ) JA enhances NO synthesis in guard cell; ( ii ) both JA and NO induced stomatal closure, and had dose response to their effects; ( iU ) there are synergetic correlation between JA and lower NO concentration in regulation of stomatal movement; (iV) JA-induced stomatal closure was largely prevented by 2-phenyl-4,4,5,5-tetramethylimidazoline-l-oxyl-3-oxide (PTIO), a specific NO scavenger. An inhibitor of NO synthase (NOS) in mammalian cells, N^G-nitro-L-Arg-methyl eater (L-NAME) also inhibits plant NOS, repressing JA-induced NO generation and JA-induced stomatal closure. We presumed that NO mainly comes from NOS after JA treatment.     

Ca2+在H2O2促进蚕豆气孔关闭过程中的作用

利用表皮生物分析法,通过表皮条缓冲液中加CaCl2研究了Ca＾2＋在H2O2促进蚕豆气孔关闭过程中的作用．研究发现在不同浓度的H2O2溶液中加入0．05mol/L和0．005mol/L CaCl2均能加强H2O2对蚕豆气孔关闭的促进作用,H2O2和Ca^2 浓度越高,气孔开度减小越明显．推测在H2O2促进蚕豆气孔关闭过程中,保卫细胞质中Ca^2 浓度升高时的来源可能是质外体中的Ca^2＋．     

干旱条件下蚕豆光合和生理特性变化研究

通过盆栽控制水分试验方法,对土壤适宜含水量(90%fθ)、轻度干旱(70%θf)、中度干旱(50%θf)和重度干旱(30%fθ)4种水分条件下蚕豆叶片光合和生理特性进行了系统研究.结果表明:随着干旱程度加重,蚕豆叶片净光合速率(Pn)、蒸腾速率(Tr)和气孔导度(Gs)受到了明显抑制,细胞间隙CO2浓度(Ci)则先升高后下降再上升;随着胁迫时间的延长,蚕豆叶片细胞膜透性、丙二醛(MDA)含量和渗透调节物质含量明显增加,叶片内的相对含水量和叶绿素含量减少,保护酶系统(SOD,POD,CAT)活性随着胁迫时间的延长,总体表现为先升高后降低.     

春蚕豆试管苗炼苗和移栽技术研究

通过对春蚕豆试管苗炼苗方法与移栽技术的研究，总结出一套蚕豆试管苗炼苗移栽的工艺流程；采用闭口一开口炼苗方法后，试管苗长势好，抗性强，成苗率达90％以上。     

Na2CO3胁迫对蚕豆幼苗几种生理生化指标的影响

用Na2CO3处理蚕豆幼苗,处理浓度为25,50,75,100mmol／L,胁迫6天后取样,测定植株鲜干重、肉质化程度、细胞膜透性、丙二醛含量、脯氨酸含量叶绿素含量等生理指标．结果表明,一定浓度的Na2CO3促进了蚕豆幼苗鲜干重、肉质化程度、叶绿素含量的增加,100mmol／LNa2CO3处理明显抑制了蚕豆幼苗的生长．Na2CO3浓度超过75mmol／L时,蚕豆幼苗MDA含量急剧上升,质膜透性也明显增加,脯氨酸含量增加明显．     

水分胁迫对蚕豆（Vicia faba L.）光合作用及产量的影响

以重庆市的蚕豆当家品种香珠豆为材料,通过人工水分胁迫处理,发现随土壤干旱程度的增加,蚕豆叶片的净光合速度下降,光饱和点降低,光补偿点提高,CO2补偿点提高,光呼吸增大;生长减弱,同化产物的积累减少,最终表现为植株的株高、根长、鲜干重、叶面积、根瘤的数量与重量、开花数、结荚数都明显下降,根冠比则上升。这是导致生物量积累减少的主要原因。     

Ca^2＋ is involved in muscarine-acetylcholine-receptor-mediated acetylcholine signal transduction in guard cells of Vicia faba L.

Acetyicholine (ACh) is an important neuro-chemical transmitter in animals; it also exists in plants and plays a significant role in various kinds of physiological functions in plants. ACh has been known to induce the stomatal opening. By monitoring the changes of cytusolic Ca^2 with fluorescent probe Fiuo-3 AM under the confocal microscopy, we found that exogenous ACh increased cytosolic Ca^2 concentration of guard cells of Vicia faba L. Muscarlne, an agonist of muscarine acetyicholine receptor (mAChR), could do so as well. In contrast, atropine, the antagonist of mAChR abolished the ability of ACh to increase Ca^2 in guard cells. This mechanism is similar to mAChR in animals. When EGTA was used to chelate Ca^2 or ruthenium red to block Ca^2 released from vacuole respectively, the results showed that the increased cytosolic Ca^2 mainly come from intracellular Ca^2 store. The evidence supports that Ca^2 is involved in guard-cell response to ACh and that Ca^2 sigual is coupled to mAChRs in ACh signal transduction in guard cells.     

Isolation and expression of an aquaporin-like gene VfPIP1 in Vicia faba

Stomatalporesintheepidermisofplantleaves consistofapairofguardcells.Stomatalclosureor openinginfluencesphotosynthesisandtranspirationof plants.Watertransmembraneintooroutofguard cellscanleadtoturgorchangeandstomatalmove ment.Originally,peopletookitforgrantedthatthe waterphysicallypassesthroughthemembranebilay ersintooroutofcells.However,water transport ratebythepassageisverysmall.Thediscoveryof plantaquaporinsgivesanewideaforexploringthe regulationofwater transmembranemovementin stomatalmovem…     

低浓度二氧化硫引起蚕豆叶片过氧化氢累积及几种清除剂变化的研究

低浓度ＳＯ２（０．２６０、０．１３１ｍｇ／ｍ３）处理蚕豆植株，引起叶片内Ｈ２Ｏ２含量升高，Ｈ２Ｏ２含量的升高与ＳＯＤ活性升高有关。同时体内清除Ｈ２Ｏ２的过氧化物酶和抗坏血酸过氧化物酶活性上升，而抗坏血酸含量下降。     

蚕豆(Vicia faba L.)叶片蒸腾速率的因子分析

利用LI－1600稳态气孔计测定了蚕叶片蒸腾速率的日变化,以及水分胁迫下蒸腾速率的变化,探讨了环境因子对蚕豆叶片蒸腾速率的影响,结果表明,光量子通量密度是影响蒸腾速率的主要气象因子,土壤含水量影响叶片相对含水量,并通过气孔扩散阻力来影响蒸腾速率。     

蚯蚓浸膏对环磷酰胺诱发的蚕豆根尖细胞变异的保护作用

以蚕豆根尖为材料，研究了赤子爱胜蚓浸膏对环磷酰胺诱变的保护作用．结果表明，用赤子爱胜蚓浸膏处理后，可以降低由环磷酰胺诱发的蚕豆根尖细胞微核率和染色体畸变率．１％蚯蚓浸膏处理组与阳性对照组相比，微核率和染色体畸变率分别降低７０２１％和４５３６％；０５％蚯蚓浸膏处理组，微核率和染色体畸变率分别降低４６３９％和３８３９％；０１％蚯蚓浸膏处理组，微核率和染色体畸变率分别降低２９８８％和２６８６％．     

活性氧与NO在SO2诱导蚕豆气孔运动中的作用

以蚕豆叶表皮为材料,研究SO2胁迫时叶面气孔运动及其调节途径.研究发现,用浓度1～200μmol/L的SO2衍生物(亚硫酸钠与亚硫酸氢钠混合液)处理蚕豆叶下表皮后,气孔开度明显减小,气孔保卫细胞内活性氧(ROS)、一氧化氮(NO)和钙离子(Ca2+)水平显著升高.采用抗氧化剂抗坏血酸和过氧化氢酶,钙离子干扰剂EGTA和LaCl3,以及NO合成抑制剂NaN3与NO清除剂c-PTIO,分别与SO2衍生物同时作用时,SO2诱发的气孔关闭效应得到有效缓解,保卫细胞内ROS、NO和Ca2+水平随之改变.抗氧化剂和NO干扰剂能阻止SO2诱导的胞内ROS、NO和Ca2+水平升高;EGTA和LaCl3能降低SO2诱导的胞内NO和Ca2+升高,但不影响ROS水平.研究结果表明,较高浓度SO2能诱导气孔关闭,SO2胁迫诱导ROS和NO合成增加,ROS和NO通过钙信号系统调节气孔开度.     

Involvement of carbon monoxide produced by heme oxygenase in ABA-induced stomatal closure in Vicia faba and its proposed signal transduction pathway

Carbon monoxide (CO) has recently proven to be an important bioactive or signaling molecule in mammalian cells. Its effects are mainly mediated by nitric oxide (NO) and cyclic GMP (cGMP). In Vicia faba leaves, CO production and heme oxygenase (HO) activity, an important CO synthetic enzyme, are first reported to increase in response to ABA treatment, which could result in stomatal closure. Inter- estingly, ABA-induced stomatal closure in V. faba guard cells is partially blocked when the synthetic CO inhibitor ZnPP, or the CO/NO scavenger Hb is added. Furthermore, we show that, exogenously applied CO donor, hematin, and CO aqueous solution not only result in the enhancement of CO release, but also time-dependently induce stomatal closure, and the latter is mimicked by the application of an NO donor SNP. The above-mentioned stomatal closure effects are differentially reversed by the addition of tungstate, a potent inhibitor of NO synthetic enzyme nitrate reductase (NR), the specific NO scavenger cPTIO, ZnPP, or Hb. During treatment for 4 h, SNP, 0.01% CO aqueous solution or hematin significantly triggers NO synthesis, whereas cPTIO, or tungstate approximately fully inhibits NO fluorescence. Ad- ditionally, application of the GC inhibitor ODQ blocks CO-induced stomatal closure. This inhibition could be reversed when 8-Br-cGMP is added. Thus, the above results suggest that CO produced by HO is involved in ABA-induced stomatal closure, and NO and cGMP may function as downstream interme- diates in the CO signaling responsible for stomatal closure.     

重金属铅和汞对蚕豆根尖细胞的微核效应

以蚕豆根尖为试材,不同浓度的醋酸铅和氯化汞为受检物,探讨重金属Pb2+和Hg2+对蚕豆根尖细胞的微核效应。结果表明:Pb2+和Hg2+均能诱发蚕豆较高的微核率,且微核率随溶液浓度升高而增加,但当高于一定浓度后,微核率反而有下降的趋势。因此,蚕豆可以作为快速检测环境中Pb2+和Hg2+遗传毒性的材料。     

叶面施硼对蚕豆生物效应的影响

用不同浓度的硼酸溶液在蚕豆不同生长期进行叶面喷施.结果表明,在蚕豆生长的幼苗期、现蕾期和开花期叶面喷施0.1%-0.2%的硼酸溶液能促进蚕豆的生长和产量的增加.可能施硼后导致蚕豆叶片的SOD活性和CAT活性的增强,同时降低了O2-生成速率和MDA含量.     

影响蚕豆（Vicia faba L.）叶片蒸腾速率的几个因子

利用LI-1600稳态气孔计测定了蚕豆叶片蒸腾速率的日变化以及水分胁迫下蒸腾速率的变化,探讨了环境因子对蚕豆叶片蒸腾速率的影响。结果表明,光量子通量密度是影响蒸腾速率的主要气象因子,土壤含水量影响叶片的相对含水量,并通过气孔扩散阻力来影响蒸腾速率。     

玄武湖水、金川河水诱发的蚕豆根尖细胞微核

玄武湖、金川河分别是南京著名的风景地和重要的环城河流，多年来玄武湖、金川河的水质污染越来越引起人们的重视．南京市内不少工厂的工业废水及居民的大量生活污水流入其中，特别是有毒物质，包括酚、苯、汞、氰化物、直链烷基苯磺酸钠、有机磷等．这些物质对人体健康的远期效应倍受人们关注．为此对玄武湖水、金川河水引起蚕豆根尖细胞染色体损伤所产生微核的情况进行了研究，就二处水样对生物体的致突变性及对人体健康的潜在危害进行了讨论     

蒙古高原野豌豆属植物区系生态地理分布研究

由于蒙古高原位于亚洲温带地区,广布的北温带和温带亚洲成分（5种,占31.25％）构成了该属的基本成分,在蒙古高原的北部汉入欧洲－后利业成分（4种）,在东部渗入了东亚区系成分（4种）,分别占25％,反遇了该属植物区系成分与西伯利亚和东亚森林区植物区系的紧密联系,亚洲中部成分（3种,占18.75％）,特别是达乌里－蒙古种（2种）为蒙古原物有种,这是该属植物在蒙古高原长期适应演化的结果,蒙古高原野豌豆属植物与东西伯利亚、东北和华北地区联系较为紧密。     

8-羟基喹啉和对苯二酚诱导蚕豆根尖细胞异常性的比较研究

采用8-羟基喹啉与对苯二酚处理蚕豆根尖,根尖经恢复培养后,以孚尔根染色法制片观察.同时以低温处理的相同材料为对照.经2种药物不同浓度处理后观察其根尖细胞的微核率,以及它们对有丝分裂指数的影响,同时还观察了它们对染色体畸变的效应.得出以下结果:(1)2种诱变剂均能诱发高频率的微核细胞;8-HQ还可以产生较高频率的双核细胞.(2)HQ在2个不同处理浓度均可明显提高有丝分裂指数,且可有效地积累中期分裂相;而8-HQ对有丝分裂指数的提高影响不明显,且在0.004 mol.L-1浓度时对有丝分裂指数具有显著的抑制效应.(3)2种诱变剂均能导致染色体畸变及其他核异常.本研究结果表明8-HQ和HQ均是细胞板有效的抑制剂和诱发染色体数目和结构变异较强的诱变剂.